1. Field of the Invention
The present invention relates to an information processing apparatus, a melody line extraction method, a bass line extraction method, and a program.
2. Description of the Related Art
Recently, attention is being paid to a technology for extracting, from arbitrary music data, feature quantity (also referred to as “FQ”) unique to the music data. The unique feature quantity, which is the subject here, includes the cheerfulness of the music piece, the beat, the melody part, the bass part, the chord progression, or the like, for example. However, it is extremely difficult to directly extract the feature quantity from the music data. With regard to a technology for extracting the melody part and the bass part from music data, JP-A-2008-209579 and JP-A-2008-58755 disclose technologies for estimating the pitch of a melody part or a bass part from an acoustic signal simultaneously including voice and sounds of a plurality of types of instruments. Particularly, the technologies disclosed in the documents are for estimating the pitch of a melody part or a bass part by using an expectation-maximization (EM) algorithm.